Gateway device for machine-to-machine communication with dual cellular interfaces

ABSTRACT

Gateway devices can use dual cellular interfaces to provide reliable communications for client machines. A gateway device can use one of the dual cellular interfaces as a primary interface and the other as a hot backup interface. The backup interface remains connected to a cellular network while communications are routed on the primary interface. Accordingly, the gateway device can rapidly switch communications between from the primary interface to the backup interface. Applications, for example, for ATM payment processing, vending machine telemetry, point of sale payment processing, kiosk internet connectivity, remote monitoring and control, mobile or electronic health, and remote information displays, may run on the gateway devices, on servers, on user devices, or a combination of these devices.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/257,548, filed on Jan. 25, 2019 and entitled “Gateway Device forMachine-to-Machine Communication with Dual Cellular Interfaces,” whichis a continuation of U.S. patent application Ser. No. 15/627,206, filedon Jun. 19, 2017 and entitled “Gateway Device for Machine-to-MachineCommunication with Dual Cellular Interfaces,” issued Jan. 29, 2019 asU.S. Pat. No. 10,194,340, which is a continuation of U.S. patentapplication Ser. No. 15/046,876, filed Feb. 18, 2016 and entitled“Gateway Device for Machine-to-Machine Communication with Dual CellularInterfaces,” issued Jun. 20, 2017 as U.S. Pat. No. 9,686,184, which is acontinuation of U.S. patent application Ser. No. 14/255,827, filed Apr.17, 2014 and entitled “Gateway Device for Machine-to-MachineCommunication with Dual Cellular Interfaces,” issued Apr. 5, 2016 asU.S. Pat. No. 9,307,344, which claims the benefit of U.S. provisionalpatent application Ser. No. 61/813,066, filed Apr. 17, 2013 and entitled“Gateway Device for Machine-to-Machine Communication with Dual CellularInterfaces,” each of which are hereby incorporated by reference.

BACKGROUND

The present invention generally relates to the field of communicationsystems and more specifically to systems and methods formachine-to-machine communication with dual cellular interfaces.

The use of machine-to-machine (M2M) systems has and will continue toincrease. Machine-to-machine systems may also be referred to as theInternet of things. Communications between devices in amachine-to-machine system can use a gateway device. In addition toproviding communications, the gateway device may provide additionalservice is such as running applications. Present gateway devices mayhave shortcomings; for example, in some circumstances theircommunications may not be sufficiently reliable.

SUMMARY

In an aspect, a gateway device is provided. The gateway device includes:a first cellular communication module configured to communicate with afirst cellular network; a second cellular communication moduleconfigured to communicate with a second cellular network; at least onelocal communication module configured to communicate with one or moreclient machines; and a processor coupled to the first cellularcommunication module, the second cellular communication module, and theat least one local communication module, the processor arranged foroperating one of the first cellular communication module or the secondcellular communication module as a primary interface and the other oneof the first cellular communication module or the second cellularcommunication module as a hot backup interface to route communicationswith one or more client machines.

In another aspect, a method for use in providing machine-to-machinecommunications for a client machine using a gateway device having afirst cellular communication module operable to communicate with a firstcellular network and second cellular communication module operable tocommunicate with a second cellular network is provided. The methodincludes: selecting one of the first cellular communication module orthe second cellular communication module as a primary interface and theother one of the first cellular communication module or the secondcellular communication module as a backup interface; routingcommunication with the client machine over the primary interface whilemaintaining the backup interface actively connected to its respectivecellular network; monitoring communications on the primary interface;determining whether communication with the client machine should switchfrom the primary interface; routing communication, after determiningthat communication with the client machine should switch from theprimary interface, with the client machine over the backup interface.

In another aspect, a gateway device is provided. The gateway deviceincludes: a first network communication module configured to communicatewith a first network; a second network communication module configuredto communicate with a second network, wherein one of the first networkcommunication module or the second network communication module is aprimary interface and the other one of the first network communicationmodule or the second network communication module is a hot backupinterface; at least one local communication module configured tocommunicate with one or more client machines; a route switch moduleconfigured to route communications with one or more client machines overthe first network communication module or the second networkcommunication module.

Other features and advantages of the present invention should beapparent from the following description which illustrates, by way ofexample, aspects of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The details of the present invention, both as to its structure andoperation, may be gleaned in part by study of the accompanying drawings,in which like reference numerals refer to like parts, and in which:

FIG. 1 is a block diagram of a communication system using a gatewaydevice with dual cellular interfaces according to a presently disclosedembodiment;

FIG. 2 is a functional block diagram of an gateway device according to apresently disclosed embodiment;

FIG. 3 is a flowchart of a process for managing communications on dualcellular interfaces according to a presently disclosed embodiment; and

FIGS. 4 and 5 are diagrams of a gateway device from a family of gatewaydevices according to a presently disclosed embodiment.

DETAILED DESCRIPTION

The detailed description set forth below, in connection with theaccompanying drawings, is intended as a description of variousconfigurations and is not intended to represent the only configurationsin which the concepts described herein may be practiced. The detaileddescription includes specific details for the purpose of providing athorough understanding of the various concepts. However, it will beapparent to those skilled in the art that these concepts may bepracticed without these specific details. In some instances, well-knownstructures and components are shown in simplified form in order to avoidobscuring such concepts.

The present disclosure describes a family of gateway and router devices.The devices can be used to provide reliable communication for paymenttransactions. The devices may be referred to as gateway devices,SysLINKs, SmartHubs, or Systech Financial Gateways (SFGs). Otherapplications for the gateway devices include secure cellular andInternet access for ATM payment processing; vending machine telemetry;point of sale (POS) payment processing and internet connectivity; kioskinternet connectivity, remote monitoring and control; mobile orelectronic health; and remote information displays. Gateway devices alsosupport home and building security and automation applications. Furtherapplications include mobile merchants, mall kiosks, major events,seasonal sales, outdoor markets, etc. The applications may run on thegateway devices, on servers, on user devices, or a combination of thesedevices.

FIG. 1 is a block diagram of a communication system using a gatewaydevice with dual cellular interfaces according to a presently disclosedembodiment. The gateway device 110 communicates with a first cellularnetwork 121 and a second cellular network 122, for example, to provideservices that allow payment transactions to succeed with a high degreeof probability. The first cellular network 121 and the second cellularnetwork 122 may be independent mobile networks. The services may haveassociated SLAs (service level agreements) that guarantee servicecharacteristics (e.g., delays, frequency and duration of outages). Forpayment transactions, availability of services can be of particularimportance. In other systems, one or both of the first cellular network121 and the second cellular network 122 may be a non-cellular network;for example, the gateway device 110 may communicate using DSL, DOCSIS,MMDS, WiMAX, or other technologies.

The gateway device 110 communicates via a local network 140 with variousmachines. The machines that communicate with the gateway device 110using the local network 140 may also be referred to as client machines,client devices, or clients. In the example system of FIG. 1, the clientmachines that communicate with the gateway device 110 include a personalcomputer 151, a thermostat 152, an alarm 153, and an automatic tellermachine (ATM) 154. Some of the devices may be collocated; for example,the gateway device 110 may be located in the automatic teller machine154. The local network 140 may be, for example, a wired network such asEthernet, a wireless network such as Wi-Fi, or a combination ofnetworks.

FIG. 2 is a functional block diagram of a gateway device according to apresently disclosed embodiment. The gateway device of FIG. 2 can be usedto implement the gateway device 110 of the system of FIG. 1. The gatewaydevice of FIG. 2 includes a processor module 225. The processor module225 is coupled to a first cellular communication module 211, a secondcellular communication module 212, a wired communication module 241, awireless communication module 242, and a memory module 235.

The first cellular module 211 and the second cellular module 212 areconfigured to transmit and receive communications with cellularnetworks. For example, the first cellular module 211 may communicatewith the first cellular network 121 via communication link 131 and thesecond cellular module 212 may communicate with the second cellularnetwork 122 using communication link 132. The first cellular module 211and the second cellular module 212 may also be referred to as networkcommunication modules. In alternative embodiments, the networkcommunication modules may use communication technologies other thancellular. For example, a network communication module may communicateusing DSL, DOCSIS, MMDS, WiMAX, or other technologies. Additionally, anetwork communication module may use a local network connection (e.g.,an Ethernet connection) to another device that then communicates with anInternet service provider, wide area network, or some other network. Thecellular interfaces may use different underlying technologies, such asPPP, LTE, CDMA, and EVDO. The first cellular module 211 and the secondcellular module 212 may use subscriber identification module (SIM) cardsto identify and authenticate the gateway device to the cellularnetworks. The gateway device may, accordingly, have two SIM card slots.

The gateway device can provide connections to the Internet for machinesthat communicate with the gateway device via the wired communicationmodule 241 or the wireless communication module 242. The wiredcommunication module 241 or the wireless communication module 242 mayalso be termed local communication modules. The gateway device providesthe connections to the Internet using the first cellular module 211 andthe second cellular module 212. The gateway device includes one or moreantennas for transmission and reception of radio signals.

The wired communication module 241 and the wireless communication module242 are configured to transmit and receive communications with clientmachines. In the system of FIG. 1, for example, the wired communicationmodule 241 may communicate with the automatic teller machine 154 and thepersonal computer 151 and the wireless communication module 242 maycommunicate with the thermostat 152 and the alarm 153.

The processor module 225 can process communications being received andtransmitted by the gateway device. The memory module 235 stores data foruse by the processor module 225. The memory module 235 may also be usedto store computer readable instructions for execution by the processormodule 225. The computer readable instructions can be used by theprocessor module 225 for accomplishing the various functions of thegateway device. The memory module 235 or parts of the memory module 235may be a non-transitory machine readable medium. For conciseexplanation, the gateway device or embodiments of it are described ashaving certain functionality. It will be appreciated that in someembodiments, this functionality is accomplished by the processor module225 in conjunction with the memory module 235, and the communicationmodules. Furthermore, in addition to executing instructions, theprocessor module 225 may include specific purpose hardware to accomplishsome functions.

The gateway device may perform operations to enhance reliability ofcommunications with the devices connected to the gateway device. Forexample, the gateway device can monitor and analyze the reliability ofcommunications with the first wireless network 121 and the secondwireless network 122 and switch between them accordingly.

The first cellular module 211 and the second cellular module 212 mayalso be termed network interfaces. The gateway device can operate one ofthe network interfaces as a primary interface while the other networkinterface is operated as a hot backup (or “secondary”) interface. Thetwo network interfaces may, for example, connect to different cellularservice providers. The first cellular module 211 and the second cellularmodule 212 may be physically separate modules or may be a single modulewith dual cellular interfaces.

The use of two cellular interfaces can greatly improve the availabilityof communication services. That is, the gateway device may determinethat communication on one of the interfaces is unavailable or unreliableand switch to using the other interface. Usage of the two cellularinterfaces may also be based on other criteria, for example, cost of thecorresponding cellular data plans.

FIG. 3 is a flowchart of a process for managing communications on dualcellular interfaces according to a presently disclosed embodiment. Theprocess may be performed by the gateway device of FIG. 2. The gatewaydevice can have two network interfaces active simultaneously. Althoughboth network interfaces are active, only one network interface isordinarily used for network traffic and the other network interface isidle. Alternatively, the gateway device may operate with only thenetwork interface used for routing communications active. Whether thenetwork interface that is not used for routing communications is activeor passive may be configured by a user. By having two cellularinterfaces connected, the gateway device can switch between theinterfaces with little delay. In the system of FIG. 1, for example, thegateway device 110 may be operating with communication link 131 to thefirst cellular network 121 as the primary interface and communicationlink 132 to the second cellular network 122 as the backup interface. Thedefault route may be through the primary interface. Alternatively, thedefault route may use the last interface that was active.

In step 310, the gateway device 110 monitors the primary cellularinterface. For example, periodically the gateway device 110 may test theprimary interface to be sure network traffic is still occurring.

If the process determines, in step 320, that the gateway device shouldstop using the primary interface, the gateway device switches, in step330, the default route to the hot backup interface; otherwise, theprocess returns to step 310 to further monitor the primary cellularinterface. The process may determine that that the gateway device shouldstop using the primary interface when network traffic on the primaryinterface is not occurring. Switching cellular interfaces may be termedfailover. Similarly the used of dual cellular networks may be referredto as wireless redundancy.

The gateway device can use one or more monitors, for example, a sessionmonitor module 231 and a transaction monitor module 232, to test theinterfaces. The monitoring of step 210 may be performed, for example, bythe session monitor module 231, the transaction monitor module 232, or acombination of the session monitor module 231 and the transactionmonitor module 232. The session monitor module 231 and the transactionmonitor module 232 can signal a route switch module 233 to change whichcellular interface communications are routed over. The session monitormodule 231, the transaction monitor module 232, and the route switchmodule 233 may be software modules that are stored in the memory module235 and executed by the processor module 225.

The gateway device can be used as a router to provide general access tothe Internet. Accordingly, the gateway device can act as the DHCP(dynamic host configuration protocol) server for client machines. StaticIP support is also provided. When the default route is switched, thegateway device can also update DNS (domain name system) information sothat DHCP client machines observe minimal delays in the network traffic.The gateway device maintains the network interface specific DNSinformation for the primary and backup interfaces and acts as a DNSproxy for the DHCP client devices. In this way, the appropriate DNSserver is used when switching between the primary and secondaryinterfaces. These functions may be performed by the route switch module233.

After switching to the hot backup interface in step 330, the gatewaydevice monitors, in step 340, the primary interface to determine, step350, whether the gateway device should return to using the primaryinterface. The process may determine that that the gateway device shouldreturn to using the primary interface when network traffic resumes onthat interface. The monitoring in step 340 may be the same or similar tothe monitoring performed in step 320.

The gateway device may determine that network traffic has resumed on theprimary interface by various methods. For example, the primary interfacemay be assumed to have network traffic if a connection can be completedto a server, such as a payment processor. The server may be identifiedby an IP (internet protocol) address. Testing the primary interface fornetwork traffic can be performed on a periodic basis while the hotbackup interface is being used. The gateway device can use a SystechOnline Update Protocol (SOUP) update or Light Weight Heartbeat (LWHB)feature to periodically check for SOUP configuration updates. If apermanent change to the designation of the primary/hot backup interfacesis required, the LWHB can also be used.

If the process determines, in step 350, that the gateway device shouldreturn to using the primary interface, the gateway device switches, instep 360, the default route to the primary interface; otherwise, theprocess returns to step 340 to further monitor the primary cellularinterface. The route switch in step 360 may be performed similarly tothe route switch performed in step 330. Step 330 and step 360 may beperformed, for example, using the route switch module 233.

The process of FIG. 3 may be modified, for example, by adding, altering,or reordering steps. Additionally, steps may be performed concurrently.Additional criteria for switching network interfaces may be used. Forexample, the gateway device may switch interfaces to reduce cost. In anembodiment, in step 350 the process may determine whether to return tousing the primary interface based on monitored performance of the backupnetwork rather than the primary network. Additionally, both the primaryinterface and the backup interface may be monitored concurrently withroute switching based, for example, on relative performance of the twointerfaces.

The gateway device can provide usage logging to show when each interfaceis in use. The logging may include, for example, the absolute time ofswitch and accumulated times on each interface. Some of the logginginformation may be kept local to the gateway device and other logginginformation may be transmitted to a server. For example, the absolutetime may only be available in the local log for use in troubleshooting.

The designation of which interface is the primary interface and whichinterface is the hot backup interface can be done, for example, througha gateway device configuration file. SOUP update or LWHB can beconfigured to periodically test for updates to the configuration file,including designation of the primary interface. The configuration filemay also be able to change one or more parameters of the monitors.Information about the configuration and usage of the interfaces may alsobe logged.

The gateway device of FIG. 2 may use various methods for monitoring thecellular network interfaces. The monitoring methods may be used in theprocess of FIG. 3. Two methods are described below. The session monitormethod checks network packet counts. The transaction monitor methodchecks attempted connections to external servers. The session monitormethod may be performed by the session monitor module 231. Thetransaction monitor method may be performed by the transaction monitormodule 232.

When using the session monitor method, the gateway device is notinvolved in packet traffic, unlike transaction based processing.Accordingly, the gateway device cannot guarantee transactions, but canmonitor network traffic and switch interfaces based on the monitorednetwork traffic. The amount of monitoring may be determined, forexample, based on the SLA. Excessive monitoring may cause increased datacharges on the cellular network. Under monitoring may not meet customerSLA needs.

The session monitor method checks receive and transmit packets on theprimary interface. If there are many transmit packets and few receivepackets, the session monitor can ping the DNS server on the primaryinterface. In an embodiment, the ping occurs when the number of transmitpackets is much greater (e.g., by a factor of two) than the number ofreceive packets. If ping fails, the session monitor may determine thatnetwork traffic is not occurring on the primary interface and signal aroute switch. If both transmit and receive packets are zero, it does notnecessarily indicate that network traffic is not available. Thus, thesession monitor may have a timer to ping the DNS server periodically(e.g., once an hour). The session monitor may also use determination ofa ping response failure time (when the DNS server is unreachable) thatis excessive to determine that network traffic is not available. Theperiod of the session monitor and the interface switching timedetermines the worst-case downtime. For example, if the session monitorruns every minute, the ping failure time is 1 second, and the interfaceswitch time is 2 seconds, the maximum downtime is 63 seconds. Thesession monitor may use alternate methods besides ping to determinewhether network traffic is occurring on the primary interface. Forexample, several connection tests (connecting to a server, ping, and DNSlookup) may be given a weighted value. The weighted values may be based,for example, on policies for individual users. Once the weighted valueexceeds some threshold, the gateway device would perform the switch tothe hot backup interface. These policies can be customizable based onparticular use cases.

The gateway device may take advantage of local services on the gatewaydevice like SOUP or LWHB to trigger the route switch if a failedconnection is detected by any of these services. For example, if thegateway device is processing transactions, and the transaction fails,this can trigger the route switch. Using just the session monitor, anyparticular transaction (e.g., a POS (point-of-sale) transaction or ATMtransaction) is not guaranteed; however, general connection to theInternet can be achieved.

The transaction monitor can track outbound connections from the gatewaydevice. The transaction monitor may use, for example, specialized codethat runs as a kernel driver monitoring network traffic. This code canbe configured to track outbound connections attempted to specific portson specific external servers (e.g., a payment processor site). Morespecifically, the transaction monitor can detect TCP (transmissioncontrol protocol) SYN/ACK handshakes for one or more IP addresses. If afailed connection is detected, a signal is generated to switch networkinterfaces. The transaction monitor continues to check for failedconnections to the payment processor. Any failed connections while onhot backup may be ignored or could trigger a switch back to the primaryinterface. The transaction monitor method may, in some embodiments,provide a better way to increase the probability that POS or ATMtransactions to a specific payment processor will succeed. However,general access to the Internet may not be improved over the sessionmonitor method since only specific ports and servers are monitored.

The gateway device, in an embodiment, may use the session monitor andthe transaction monitor at the same time. Either monitor can trigger aswitch to the hot backup interface. Additionally, a change to theconfiguration file on the SOUP server will be detected by SOUP update orLWHB, which may result in a change of the primary/hot backup interfacedesignation.

The gateway device configuration file provides a method, among otherthings, to switch the primary/hot backup priority. Which interface ispreferred may be changed, for example, to take advantage of potentialcost differential between two carriers associated with the cellularinterfaces. The configuration file determines which interface is primaryand which is the hot backup. Additionally, the configuration file cancontain timer information related to the monitor periods. Thisconfiguration file is typically updated on a 24 hour cycle. Through theuse of the Light Weight Heartbeat (LWHB), this time period can bereduced. For example, the gateway device can be configured to use LWHBto check every 15 minutes against the SOUP server. If the primary/hotbackup needs to be switched, the LWHB would indicate a full check-in isneeded, resulting in an updated configuration to the gateway device.

Additionally, the gateway device can record the usage of the primary andhot backup interfaces and upload this information to the SOUP server ona period (e.g., daily cycle).

The gateway devices can operate in many scenarios. In a first exampleusage case, a network operator (e.g., a mobile virtual network operator(MVNO)) wants to change the order of preference of network use, makingthe current primary network the secondary network and vice versa. Thenetwork operator may want to do this for a subset or for the entireuniverse of dual network gateway devices that the network operator uses.In this example usage case, this is a permanent change rather than atemporary change, for example, because of network session failure ortransaction failure. The network operator also wants to be able tochange other configuration file settings.

The network operator can achieve the change in order of preference ofnetwork use my multiple methods. In a first method 1, the SOUP server isused to change the preference in the configuration file for the primaryand hot backup interfaces, making Carrier 1 the hot backup and Carrier 2the primary network. The gateway device can be configured for the SOUPupdate or LWHB to periodically contact the SOUP server for aconfiguration update.

A second example usage case illustrates a scenario where a transactionfails. Here, the transaction monitor signals a route switch so that thehot backup interface is used rather than the primary interface. When theprimary network recovers (e.g., as determined by a ping test orconnection to the payment processor) the primary network interface isagain used.

The gateway device of FIG. 2 and the related methods and communicationsystems are susceptible to many variations. Additionally, for clear andbrief description, many descriptions of the systems and methods havebeen simplified. For example, the figures generally illustrate one or afew of each type of device (e.g., two cellular communication modules,one wireless communication module), but a gateway device may have manyof each type of device. Similarly, many descriptions use terminology andstructures of a specific wireless standard. However, the disclosedsystems and methods are more broadly applicable.

Implementations of a gateway device may include many features inaddition to those described above. In various embodiments, gatewaydevices and the systems in which they are used may include variouscombinations of hardware/firmware features, cloud-based and local serverfeatures, and smart phone features.

Examples of hardware/firmware features include: hardware upgrade slotsthat support cellular modules and/or other hardware options and futurehardware features; support for 2G through 4G (e.g., CDMA, EVDO, LTE,GSM, 1×RTT, SPA+) cellular performance or other future cellulartechnologies; one or multiple Ethernet ports (e.g., using wiredcommunication module 241 or the like), with multiple independent IPaddresses when the gateway device has more than one Ethernet port; zeroor multiple POTS (plain old telephone service) ports (e.g., v.90, v.92);zero or multiple serial ports (with RS232, RS422 and/or RS485 physicalinterfaces) that may be configured as standard serial ports (forapplications such as POS and security) or as DEX & MDB ports (forvending applications); zero or multiple USB (universal serial bus)ports; zero or multiple microSD (or other types memory card) slots;support for various local wireless technologies including Wi-Fi (e.g.,802.11 a/b/g/n), ZigBee, Z-Wave, Bluetooth, NFC, ANT, etc.; temperatureand motion sensors; zero to multiple connectors for external generalpurpose 10 using a GPIO and/or I²C interface; an external or internalbackup battery; and support for local applications.

Examples of cloud-based and local server features include: provisioning;configurable alerts (for reporting errors, location, motion, batterystatus, etc.); Wi-Fi hotspot; a consumer quality GUI for status andcontrol; vending software; building security software; and an objectoriented GUI interface that can be used by an unsophisticated user.

Examples of smart phone features (which may be used with other userdevices, e.g., tablet and notebook computers) include: a web-driven GUIinterface; and a custom app-driven GUI interface.

Gateway device may be provided in many product configurations. A familyof gateway device products includes multiple enclosures that providemaximum flexibility in providing multiple configuration options. Thespecific options which are enabled for any one configuration can becontrolled by the physical presence of the hardware features or can beset, locally or remotely, by electronic configuration, which isindependent of the actual presence of physical hardware. The number ofdifferent hardware configurations may be established based on economiesof scale through manufacturing of standardized configurations balancedby the additional costs which will be driven by the presence of someunnecessary hardware for specific configurations.

An example gateway device family includes four subfamilies: The SysLINK1000 is a low cost, single purpose gateway that will typically be usedfor simple bridging applications as well as for simple ATM or vendingapplications. A SysLINK 1000 will generally be placed near the targetapplication. The SysLINK 2000, SysLINK 3000 and SysLINK 4000 are allfully featured general purpose gateways, bridges or routers that supportthe connection of multiple devices across multiple local or remotenetworks. They are used in multi-purpose home and building applicationsand often placed in a central location (such as a wiring closet) withhome runs to the target applications. The family of gateway devices cansupport combinations that include multiple local network connections andmultiple broadband networks for internet connectivity. The gatewaydevices may be co-located with other gateway devices of the same ordifferent subfamilies. Across subfamilies, the gateway devices may havesubstantially the same appearance, although the physical dimensions ofthe devices may vary, for example, driven largely by the number ofcommunication interfaces that are provided by a particular device.

Gateway devices may be provided with various levels of communicationsperformance. Many applications for gateway devices require data ratesthat are no higher than 0.05 Mb/s (megabits per second). This is wellwithin the range that is supported by 2G cellular technology. However,other applications require faster performance, which can be provided by3G or 4G cellular technology. For example, kiosks, home gateways anddigital signage applications may require real-time multimedia streaming.

The architecture of the gateway devices, in an embodiment, is designedto permit field upgrade of an installed device from a slower speedtechnology to a higher speed technology or the addition of an additionalnetwork module by a user with little or no training. This architecturehas been constructed to accept cellular modules from multiple sourceswith minimal development. The architecture supports future cellulartechnologies as well as the existing technologies previously mentioned.

Some bridging applications do not use cellular connectivity (such asWi-Fi to Ethernet). In these applications, performance will match theunderlying physical interface and will be minimally throttled by thegateway device.

Example applications for gateway devices include: ATMs with non-GPS(global positioning system) based location services and motion detection(including tilt) that will provide alerts (e.g., page, text, MSG, email,tweet, audible alarm, etc.) for unauthorized motion; ATMs with GPS basedlocation services, motion, and temperature sensing; ATMs bundled withWi-Fi hotspot services with GPS based location services, motion, andtemperature sensing; home and building automation for lights, locks,HVAC (heating, ventilation, and air conditioning), and smart grid energymonitoring, controlled through a smart phone application; vendingservices with support for credit card transactions and inventorymonitoring; security services; video surveillance; environmental orsecurity alarm box monitoring; fax gateway; and building services withpool/spa, irrigation, and alarm monitoring.

Gateway devices may connect to different types of servers via theInternet or other networks. A wide variety of client machines, such asutility meters, telephones, kiosks, smart phones, thermostats, facsimilemachines, motion sensors, and alarms may be connected to one gatewaydevice. Each of these devices could be connected through a different,normally incompatible, network. The gateway device can be used tocommunicate information to and from those devices that have been coupledto the gateway to one or more Internet-based servers. An individual canaccess the information, for example, via a notebook, smart phone,desktop or tablet computer.

Gateway devices can be provided in many physical forms. In variousembodiments, gateway devices have the following physical features orsubsets thereof. Devices may be placed on a flat surface (desk, shelf,etc.), wall mounted, rack mounted, and/or magnetically mounted to ametal surface. A gateway device may have one or more I/O connectionsand/or power inputs on the rear of its enclosure. Lights and buttons maybe facing the front. One or more antennas, when present, may be attachedto both sides of the gateway device gateways and may be user adjustable,for example, up to 270 degrees in three planes.

The power input may be drawn from an AC outlet or from a DC source, forexample, 4.5 V to 30 V DC. The power input can use a locking powerconnector to provide increased reliability. Devices may include arecessed reset push button facing the front of the unit. Additionalantennas for other wireless communication modules may be located insidethe enclosure. The gateway may include SMA female and SMA maleconnectors for external antennas to support various wirelesscommunication technologies. Devices will support the use of a SIM cardif such a card is necessary to support the underlying cellulartechnology, for example, for GSM or LTE service. Devices may also usemultiple SIM cards. The multiple SIM cards may be used with the samecellular module or with different modules.

The physical enclosure for a gateway device may be physically small tosupport applications that require an embedded gateway, for example, forATM, vending and remote display applications.

Some gateway devices may include a display, for example, an LCD or touchscreen display. The display can provide a graphical user interface. Somegateway devices may also include an interface, for example, HDMI(High-Definition Multimedia Interface), to an external display.

In various embodiments, the gateway devices include option slots forconfiguring the devices with a range of features. The option slots maybe multiple types and occur in differing number in various familymembers. A motherboard may, for example, contain functions that arecommon to all or many member of a family of SysLINK gateways. Forexample, the motherboard includes a programmable processor forcontrolling communication operations and directing traffic between cardspopulating the option slots.

In various embodiments, the SysLINK gateways support Ethernet networksand have the following features or subsets thereof. Ethernet ports maybe configured as a secured LAN, an unsecured LAN, or a WAN port. A WANport connects to an Internet source, such as a broadband router. Such aport may be identified as an “Internet port.” A LAN port connects to alocal network, such as an individual Ethernet-based device, a switch, ora router. Ethernet ports may operate at 10, 100, 1000 Mbps speeds orother speeds. One or more of the Ethernet ports may support power overEthernet (PoE).

The gateway devices include routing functionality to connect theprovisioned communication devices. The router functionality includessupport for firewall, DHCP, NAT, IPv4, IPv6, VPN pass through,certificate based Open-SSL, VPN, QOS, dynamic DNS, URL filtering,traffic filtering, and port forwarding.

Internet access may be provided by cellular, Ethernet, Wi-Fi, power linecommunications, satellite, dialup modem, or other communicationtechnologies. Any of these technologies can be designated as a primaryor backup connection. For devices with multiple sources of Internetaccess, the various sources are prioritized. The priority may be setautomatically or through user configuration. Gateway devices are able toaccess a backend server through routers and firewalls. Access to thebackend server may be at programmable intervals or as defined by theneeds of applications that are being executed. Some gateway devices havean always-on connection to the backend server, allowing random access tosuch devices from the server. Such an operation may be termed“on-demand.”

In various embodiments, a gateway device may include one or more POTSports for connections that use traditional analog telephone lines. POTSports may be used, for example, with FAX or ATM devices. A POTS port mayfunction as a standard phone line from the perspective of appliance thatis plugged into the gateway device. Supported MODEM standards include300 bps: V.21; 1200 bps: V.22 and FastConnect; 2400 bps: V.22bis andFastConnect; 9600 bps: V.29, V.32 and FastConnect; 14,400 bps: V.32bis;33,600 bps: V.34; 56,000 bps: V.90; V.42bis; and MNP5 data compression.The ports include on and off hook line voltage monitoring, parallelhandset (intrusion) detection, V.42 and MNP 2-4 error correction (forexample, for dial backup). A POTS port may be used to provide standardGroup 3 FAX from 300 to 14,400 bps with Class 1 command compatibility.Higher speeds may also be provided.

One or more of the POTS ports will be able to interface to a standardphone line for remote access and Internet connectivity.

A POTS port supports DTMF (dual-tone multi-frequency, includinggeneration and detection of touch tones), pulse dialing, or relevant FSK(frequency-shift keying) protocols. Functions may be programmed forcompatibility with alarm panels and/or other applications.

In various embodiments, a gateway device includes one or more serialport. The serial ports may support RS-232, for example, for alarmsystems, RS-422, RS-485, and RS-485/422/232. A serial port may operatein an asynchronous or synchronous mode. A serial port may have either aDCE or DTE physical interface. A serial port may support variousprotocols including SDLC and 3270 bisync.

In various embodiments, gateway device gateways include one or more USBports. The USB ports may, for example, be USB 2.0 ports and operate inmaster mode. A USB port may be used, for example, to connect to memorysticks, cellular modems, PIN terminals, payment terminals, and cameras.A USB port on the gateway may supply power, for example, 500 mA at 5 V,to an attached device. Some of the USB ports are accessible internally,while others are accessible externally to a gateway device. Some USBports may be directly wired to a USB slave device.

In various embodiments, gateway devices include one or more cellularinterfaces. Cellular wireless interfaces may connect to various carrierservices, for example, Verizon 2G, 3G, 4G, AT&T 2G, 3G, 4G, and Sprint2G, 3G, 4G. The cellular wireless interfaces commonly use antennas thatare external to the enclosure of the gateway device. Multiple antennasmay be used to increase reliability. Multiple antennas may be used toprovide multiple simultaneous connections. The gateway device supportslocation services through cellular services, for example, for use when aGPS location is not available. Multiple cellular interfaces may beprovided in one gateway device. In an embodiment, cellular wirelessinterfaces may be used to communicate with users with the gateway deviceproviding network communications, for example, by a wired backhaulconnection.

In various embodiments, gateway devices include Wi-Fi wirelessinterfaces may operate according to various standards, such as 802.11a,b, g, and n. A Wi-Fi interface may use one or multiple antennas. A Wi-Fimodule may support security protocols, such as WAP, WPA, WPA2, and AES,as well as new protocols as they are introduced. When a Wi-Fi wirelessinterface operates as an access point, multiple (e.g., 16 or 20)simultaneous connections are provided. A Wi-Fi interface may alsofunction as a client device, for example, when providing Internet accessto the gateway device. Many other types of wireless interfaces may alsobe included in a gateway device.

Gateway devices may also provide support for Bluetooth-based devices. ABluetooth interface may support either the Bluetooth classic orBluetooth low energy. The Bluetooth network may be used, for example, tocommunicate data to mobile phones and other Bluetooth devices. Antennasfor Bluetooth interfaces are generally inside the gateway deviceenclosure.

Gateway devices may also provide ZigBee interfaces. Supportedspecifications include ZigBee Home Automation, ZigBee Smart Energy,ZigBee Telecommunication Services, ZigBee Health Care, ZigBeeRF4CE-Remote Control, ZigBee Building Automation, and ZigBee RetailServices. A gateway device with a ZigBee interface operates as ZigBeeCoordinator (ZC) and bridges to other networks. Antennas for ZigBeeinterfaces are generally inside the gateway device enclosure.

Gateway devices may also provide Z-Wave interfaces. Antennas for Z-Waveinterfaces are generally inside the gateway device enclosure. BothZigBee and Z-Wave interface may be joined to and disconnected from otherZigBee and Z-Wave networks. A gateway device may provide simultaneousZigBee and Z-Wave support to bridge heterogeneous environments.

Support of NFC (near field communication) is also provided. The supportis internal to the gateway device in some configurations.

In various configurations, gateway devices include one or more motiondetectors. The detectors are sensitive to movement and jostling. Motiondetection is used, for example, to detect movement of a machine wherethe gateway device has been previously installed, for example, inside anATM. A motion detector may sense general physical movement as well astilting. A gateway device may provide adjustable alerts when motion isdetected. Motion sensitivity may be disabled and re-enabled via a serverto allow for legitimate movement of the device.

In various configurations, gateway devices include one or moretemperature sensors or interfaces to external temperature sensors. Atemperature sensor may have programmable sensitivity in the range of,for example, negative 25 to 100 degrees Celsius. Temperature reading maybe provided in Fahrenheit and Celsius. Alerts may be triggered based onset points, such as a minimum temperature and a maximum temperature. Anexternal temperature sensor may be useful for food storage or coldvending machine applications.

In various embodiments, gateway devices include general-purposeinput/output (GPIO) interfaces. Such interfaces may be used to interfaceto smart probes. GPIO interface signals are programmable as inputs oroutputs. Some outputs may provide normally open or normally closedconnections and may support high voltages, for example, 30 V. This maybe used to simulate an open or closed door switch. A GPIO interfacesignal may also be used to support an analog external temperaturesensor, for example, for refrigerated vending applications. GPIOinterface signals may also support I²C electrical and messagingprotocol. The GPIO interface may be optically isolated. The GPIOinterface may also be used to power on or off other devices based, forexample, on messages from a server. Other interfaces may also be used topower devices on or off.

In various embodiments, gateway devices include battery backup withinthe enclosure or, alternatively, support for an external battery backup.The battery backup will power the gateway device for at least one hour.Battery backup may be used to prevent or detect theft or tampering.Status of the battery backup may be reported to a server and may besignaled by indicator lights. Other devices may be connected to thebattery backup.

A gateway device generally includes firmware for program storage.Upgrades to the gateway's firmware may, for example, be performedthrough loading via a portable storage device that can be attached tothe gateway device (such as a USB memory stick or a micro SD card);performed over the air via a cellular or Wi-Fi network; performed via anEthernet connection; or performed by physically changing a storagedevice in the gateway device.

Many different applications may be provided by the gateway devices andthe systems in which they operate. Various applications may operate onthe gateway device, on servers communicating with the gateway device, ora combination thereof. Applications may be programmed, for example, viaC, C++, or other commonly used languages. Applications may supportobject oriented GUI interface that can be used by an unsophisticateduser to create scripts. This interface may be presented through a webinterface and a smart phone.

One type of application is for location information. Location can bederived from one or more tower cells (cell-ID) or through GPS. Thedevice will use the best source, or combination of sources to determinelocation. Examples of accuracy are tower cells—300 to 2,000 meters andGPS—10 to 300 meters.

A user can specify a geo-fence that will alert if device moves beyondthe fence. The geo-fence surrounds a specific area that is defined on amap (and configured via the backend server). Also, the geo-fence can bea circle defined by a radius that is centered at the current location(and configured locally or via the backend server). The radius can bespecified, for example, in feet, meters, miles, or kilometers from 0 to64K.

Location data may be recorded (via a snapshot) once every N seconds,minutes, or hours, for example, configurable from 0 to 1K when the unitis in a “steady-state” operation. Recordings may be stored innon-volatile memory. A device may record, for example, up to 2,880readings over a user-specified interval (e.g., 1 reading per minute for24 hours or 1 reading every 10 minutes for 1 week).

A location application may define a “high-threat” operation after motionis detected beyond a configurable threshold. A high-threat warning isenabled for a configurable number of seconds, e.g., from 0 to 64K.During high-threat mode, the location data is recorded (via a snapshot)once every N seconds, minutes, or hours, e.g., configurable from 0 to1K. The snapshot frequency may be increased during high-threat modecompared to steady-state operation. Recordings are stored innon-volatile memory.

Locations may be reported in batch to the backend server once every Nsnapshots in steady-state mode. The parameter “N” may be configured from1 to 1K. Data compression may be used to optimize reporting, especiallyif no movement is detected.

Another type of application is for alerts. Events or conditions thattrigger an alert (such as movement of the device) will producenotifications. The form of notification may be configured for varioustypes of alerts. Examples of responses include one or more notificationsvia text message, pager or email; a user-programmable C code or GUIscript; a phone call with voice prompt, and/or GPIO action (e.g., totrigger a local alarm).

Another type of application is for SmartROAM. Roaming may occur when adevice is experiencing difficulty connecting to a local cellular tower(perhaps due to high network congestion, or a weak signal), and thegateway device attempts (if configured) to use another nearby tower evenif the alternative tower is with another carrier. The gateway devicewill attempt to return to the original tower after a wait period.Roaming related events generally do not generate alerts, but may belogged.

Another type of application is for temperature. Temperature measurementsmay be from on-board temperature sensors or from external probes. Theuser may specify temperature conditions (e.g., minimum and maximumthresholds) that trigger an event.

Another type of application is for Motion. Motion applications useinformation from a motion sensor in the gateway device. An example, anapplication triggers an alert when a motion threshold is exceeded.Thresholds may be, for example, accelerations or orientation angles.

Another type of application is for POS terminals and ATMs. Theseapplications include monitoring the POS or ATM activity, initiatingcommunication to payment processors, and protocol translation forpayment processors, activity reporting, etc.

Another type of application is for abnormal transaction patterns. Suchapplications include generating alerts based on transaction patterns,e.g., a pattern of transaction processing frequency that varies from thenorm by more than a threshold.

Another type of application is for video surveillance. Videosurveillance applications generally use connectivity to Ethernet orWi-Fi. Some video surveillance applications stream from a camera to aweb-based client or app-based smart phone. Video from multiple camerasmay stream simultaneously. Video streams may be filtered to detectpredefined conditions in the video. For example, motion detection maytrigger recording and an alert notification.

Another type of application is for Wi-Fi hot spots. Features of a hotspot application may include online payment or the use of vouchers,Wi-Fi start page, custom pricing (including free), and complete billingsolutions (e.g., payments, refunds, etc.).

Another type of application is for fax. A fax application may providegateway support to allow an external fax machine connected to a POTSport to send and receive faxes to other fax machines accessible via aphone call. The faxes may be communicated by way of the Internet.

Another type of application is for voice, audio, and/or video. A gatewaydevice may provide voice communication using VOIP technology. Thegateway device may include an integral speaker and microphone or may useexternal devices couple to the gateway device via one of its ports. Insome embodiments, video conferencing is also supported. A gateway devicemay also provide audio and/or video streaming. Additionally, in someembodiments, gateway devices provide PBX functionality to a plurality ofusers.

A gateway device may also provide content management. For example, thedevice may provide digital rights management for Kindles, eReaders,iPods, Netflix, Blockbuster, etc. In an embodiment, a user can accesscloud-based content via a cellular connection from the gateway device.

A gateway device may also include a media player. The media player maypresent audio or video via integral devices or by an external devicecouple to the gateway device, for example, by an HDMI port. The mediaplayer can be used for informational displays or marketing messages.

Another type of application is for proximity. A gateway deviceapplication may initial actions based on the presence of an individualnear the gateway device or within a building or area associated with thegateway device. Uses of proximity applications include security andmarketing, such as presenting retail coupons to consumers based on theirlocation. The gateway device, in an embodiment, detects an individual'sproximity by communicating with the individual's mobile phone or similardevice.

Another type of application is for vending machines. A vending machineapplication may use, for example, Ethernet, Wi-Fi, and ZigBee interfacesto enable cross-vending machine communication and provide Internetconnectivity through one shared connection. Additional vending machineapplication features include door open, local siren, remote temperaturesensor (via the SmartPLUG), and backup battery status. Further vendingmachine application features include vending status, inventory status,funds reconciliation (e.g., via a cloud-based server, web-based client,and/or smart phone), and credit card and private card paymentprocessing.

In an embodiment, a family of gateway devices shares a modulararchitecture. Those elements common to each (or most) family members areplaced on the main board. Other features and connectivity are handled bythe addition of one or more modules. Advantages of this modular approachinclude the ability to capitalize on new device developments, toincorporate new cellular and/or wireless standards as they are deployed,to simplify configuration control, to minimize SKU growth, to simplifyinventory control, and to combine high volume feature clusters inmodules to lower cost to selected markets

One such family includes the SysLINK 1000, 2000, 3000 and 4000. Thesegateway devices include a Systech mother board (SMB). Each SMB has amain processor (e.g., 400 MHz ARM926), RAM (e.g., 256 Mbytes DDR2),flash (e.g., 256 Mbytes), and Ethernet capability. The 1000, 2000, 3000and 4000 SMBs also contain USB Host connections (e.g., a 4-port hub).These SMBs also have support for motion sensing and internal temperaturemonitoring. Some features may be depopulated in selectedimplementations. In an embodiment, the mother board may use multiplephysical boards. In some configurations, a gateway device may include adigital storage module, for example, a hard disk drive or a solid statedrive. The digital storage module may be used to store, for example,information collected by the gateway device or downloaded information,such as a movie.

Other functions on the SysLINK 1000 through 4000 can be implemented onSystech Option Cards. Systech Option “Cards” mate to the SMB via option“Slots” with 22-pin connectors. Option Cards can be physically mountedon top of the SMB. Any connectors that are necessary to connect externaldevices are located on the edge of the option card and the rear panel ofthe gateway device. Some option cards must accommodate wider connectorsthan others. For instance, DB-25 connectors are wider than DB-9connectors. To reduce or minimize the gateway device physical size, twodifferent size options slots are defined, full size and half size.Example dimensions for these cards are 56×70 mm (full size) and 28×70 mm(half size). The SMB and enclosures are laid out such that a full sizecard may only be installed in a full size slot but a half size card maybe installed in either a full size or a half size slot.

In addition to the Systech option slots, each SysLINK 1000 through 4000can support one or two Mini PCI Express daughter boards (PCIe). SIMsockets (or slots) may be provided, for example, on the gateway devicevia the PCIe board. Cellular certification is eased by mounting thecellular modem Mini PCI Express card on a carrier board that includesthe Mini PCIe connector and a SIM (designed to accommodate a specificcellular module). The other Mini PCI Express slot can be used for otherhigh speed connectivity support, such as Wi-Fi. Both of the Mini PCIExpress boards communicate via a High Speed 480 Mbs USB 2.0 interface.

Typically, one end of an option card will be secured to the motherboardwith a 22 pin header arranged as 2×11 on 0.10 inch centers, with theother end supported by standoffs. External connectors affixed to optioncards protrude through the rear of the enclosure. Systech option cardmay be, for example, a simple POTS implementation.

The option card connection is made through a 20 pin header. Thesesignals bring the host processor's SPI, I2C, USB, and UART/USART dataand clock to the board. Additionally, power, ground, and interruptrequest lines are present. The table below shows assigned connections.On some Systech cards, only pins 1 through 18 are available and pins 2and 4 are not available to carry USB data. In other embodiments, a 22pin header is used. All signal levels 3.3 V DC unless otherwiseindicated.

TABLE Daughter Board Signals Option Card Pin Header Pin SignalDescription 1 V+ Raw Supply Power 2 USB-M USB Port 3 V+ Raw Supply Power4 USB-D USB Port 5 GND Ground 6 GND Ground 7 I2C - SDA I2C Data 8 I2C -CLK I2C Clock 9 3.3 V DC Regulated 3.3 V 10 3.3 V DC Regulated 3.3 V 11TXD Serial Xmit Data 12 SPI - SCLK SPI Clock 13 RXD Serial Rev Data 14SPI - MOSI SPI Data from Host 15 CTS Clear to Send 16 SPI - MISO SPIData to Host 17 RTS Request to Send 18 /SPI - SEL Board Select - ActiveLow 19 SDC Serial Data Clock 20 /INT Interrupt Service Request 21 GNDChassis Ground 22 GND Chassis Ground

An example SysLINK gateway, designated SysLINK 3000 and illustrated inFIG. 4, has a motherboard 410 with a single Ethernet connection and asingle PCIe connection 421. The SysLINK 3000 includes four option cards451-454. The illustrated device includes an RS232 option card 453 withan extended rear portion allowing a wide DB25 connector. The adjacentoption card 454 does not include external ports, for example, a securitycoprocessor card.

Another example SysLINK gateway, designated SysLINK 4000 and illustratedin FIG. 5, has a motherboard 510 with four Ethernet connections, dividedbetween two separate networks; two PCIe slots 521-522 for cellular andWi-Fi; a full size 553 and two half size 551-552 option slots that canbe used for one or more Serial, POTS, GPIO, DEX, Zigbee or Z-Wave cards;and two externally visible USB connections for USB storage devices oradditional connectivity options.

An integrated ARM9 processor from Atmel (AT91SAM9G45) is used in some ofthe models. In addition to the processing core, it includes four USB 2.0High Speed 480 Mbs ports (particularly useful, for example, forsupporting 4G and 3G at their maximum rates), embedded NAND flashcontrol, four UART/USARTs onboard as well as a debug serial port, andadvanced power management features.

Functional and/or physical isolation may be required to pass PaymentApplication Data Security Standard (PA-DSS) compliance testing. Agateway device may thus use an isolated payment processor. Payment dataprocessed by the processor and resulting encrypted data can be passedvia a serial port or other transport medium to the mother board. Theboard handles the clear text transaction recognition, Open SSL (securesockets layer) encryption and packing and unpacking of data. This datawill then be passed through the port to gateway device for communicationusing the gateway device's preferred connectivity hierarchy.

Some gateway devices include UPS (uninterruptible power supply) andbattery backup. When the gateway device detects a slow, monotonicdecrease in supply voltage, it will assume it is running on backup powerand provide an alert message to the server. This message will indicate,based on the rate of voltage decay an estimated time to shutdown.

The gateway device firmware may be implemented using a standard embeddedoperating system, for example, Embedded Linux. When using EmbeddedLinux, some firmware using threads can be ported to Linux using the<pthreads.h> library. This library provides a POSIX compatible set ofcalls, implemented via calls to Linux kernel primitives.

Also Stream abstraction from System V, release 4 (SVR4) can be supportedunder Linux by LiS v2.19 (Linux Streams). This library implements thestreams abstraction at the user level through multitasking. It shouldfacilitate the porting of existing PPP/POTS transaction handlingfunctions to new platforms. OpenSSL code may alternatively be used toaddress this.

A Streams interface to the 3G and 4G cards may allow code for slowernetworks to work seamlessly on faster cellular networks.

Gateway devices may use a streams based M2M design. One gateway mayinclude 13 different IO modes, e.g., Ethernet, cellular, Wi-Fi,Bluetooth, ZigBee, Z-wave, DEX, MDB, motion/position, temperature,location, GPIO, and POTS. Each of those IO modes may have severalassociated device types. Even for a single device model on each IO,there are 156 (12×13) different cross connection combinations. Streambridges may be used to support all possible connections. Since many ofthese ports have many device classes that must be handled, the practicalpossible combinations can be in the thousands.

Furthermore, this assumes the gateway device is not “smart.” That is tosay, it does not have any semantic knowledge of the data it transports.This condition is clearly not the case in the payment processingapplications, nor will it be true for many emerging applications, suchas medical logging, office automation, security, and vending. Thus,firmware may be as modular, reusable, and easily validated aspractically possible.

A streams model includes a hierarchical data flow architecture. Thebasic concepts of an example firmware architecture include:

IO Streams flow bidirectionally to and from ports.

Device Abstraction Filters (DAFs) are inserted into IO Streams. Theirfunction is to intercept a subclass of data streaming from a Port(Upstream, or the left side of the filter) and route it to anotherDevice Filter or API Filter. Data that is not part of a member of thedevice subclass is passed downstream. Data streaming from downstream ofthe device to the IO port is simply passed to the device filter withoutany handling.

DAFs may be implemented, for example, in C++. In many embodiments, DAFspass and receive device data to or from other DAFs as XML text messages.The API of a DAF can be defined as an object class contained in alibrary supplied to an embedded application developer.

API Filters are connected to the Device Data port of a DAF. These objectclasses provide a uniform set of embedded Application Program Interfacesto Device Abstraction Filters. They regularize the method for sendingdata to and from a Device Abstraction and monitoring and generatingdevice events.

Device Messaging Tasks are two port processes that pass data packetsbetween a pair of device abstractions without any significantinterpretation of the contents of those packets.

Embedded Application Tasks (EATs) are tasks attach and communicate withone to many different API filters. Any API Filter may only be attachedto a single Embedded Application Task, but a single Embedded ApplicationTask may attach many different API Filters.

EATs can be implemented in virtual machines, for example, JAVA and PHP.For procedurally complex operations, JAVA may be the preferreddevelopment platform. For simpler operations transforming EATs, PHP maybe employed.

Remote JAVA debugging can be used to facilitate program development.

The firmware architecture of an example gateway device may be configuredto perform multiple functions. In this example, most upstreamcommunication is a payment processor embedded application. It takespayment requests from a local secure Ethernet or a POTS port. Thesepayments are encrypted and communicated via a cellular connection to apayment services provider. Since they are the upstream connections tomost IO streams, no data pertaining to these transactions can be visibleto filters downstream and are thus secure.

The next set of filters passes location information to an OnDemandconnection. Further downstream, an embedded application passes buildingstatus and handles building control commands with a remote buildingmanagement server. Finally, a Wi-Fi Hotspot server provides wirelessconnectivity to users, but the access is filtered and access controlledby the Wi-Fi Hotspot router application.

This modular firmware architecture can be based on porting animplementation of Linux Streams to the gateway device. Additionally,software coding, interface and tasking standards can be used to assureuniformity of filter implementation and reusability of filter componentsand tasks in different client configurations. For example, by applyingthe described methods, a new customer configuration comprised ofdifferently connected filters and tasks may require verification of theintegration but not of the individual component functionality.

The gateway device may operate with a two-step boot process. The flashmemory may be partitioned into a number of virtual Linux drives. Forexample, there can be: a Safe Boot Drive Image; a Customer Boot DriveImage; and a Data Drive Image.

The boot process can include initializing SDRAM memory and otherhardware interfaces and then checking the integrity of the Customer BootDrive Image. At a minimum, the Customer Boot image should have a goodchecksum, valid file structure, and a correct electronic signature. Ifthese conditions are met, a watch dog timer will be set and an attemptwill be made to boot the Customer Boot Drive Image. As part of theCustomer boot process, the watch dog timer is turned off after asufficient level of functionality has been initialized to insure thatthe host may be contacted and updates may be validated and downloadedwith the operating kernel.

If the watch dog timer expires prior to being turned off, the systemwill automatically boot using the Safe Boot Drive Image. Whenever theunit boots from the Safe Boot Drive, it will contact the SOUP (using,for example, Systech Online Update Protocol) server, indicate itscustomer boot failure, and wait for a new customer boot image to bedownloaded.

A short press of the RESET switch will trigger a reboot from theCustomer Boot Drive Image. A long press of the RESET switch will triggera reboot from the Safe Boot Drive Image.

The Safe Boot system will typically be configured to contact the Systechserver and perform Customer firmware update and then reboot the systemnormally.

In addition to the firmware embedded in the device, external softwarerunning on other platforms may be used for some functionality. Exampleprotocols for communication between the device and other platformsinclude SOUP, OnDemand, RM, and LWHB.

SOUP—uses HTTP/HTTPS to connect to a SOUP server, send status, and checkfor new code, configuration files, or PRL files. A unit set up for SOUPupdates is typically configured to connect to the host on boot up andthen daily during the night. It can also be configured to morefrequently send “heartbeats” (status messages) during the day.

RM—Remote Management—provides access to the web server interface on theunit. The unit makes an outbound connection to a server, sends its MACaddress to identify itself, then remains connected and waits. When aclient wants to connect to the unit, it connects to the server,identifies the unit it wants to talk to, and the server connects the twosockets. At that point, the connection operates just as if the clienthad connected to port 80 or 443 on the unit.

OnDemand—operates similarly to RM, but gives access to a port (e.g.,serial port or pots port) instead of to the web server interface.

Direct Connection—A TCP connection can be made to a physical port on thegateway device. For example, connect to TCP port 800n or 900n on theunit to talk to physical port n. Once the connection is established, thedevice can “write/send” data out the TCP connection to go out the port,and the device can “read/recv” data arriving on the physical port. The800n ports support “raw TCP”—the device doesn't touch the data, justsend/receive it as is. The 900n ports may support the “telnet” protocol.So the device looks for and processes telnet escape sequences in the TCPdata stream and generates appropriate telnet escapes to the host.

If the device is behind a firewall (e.g., for “wired” units) or on aprivate network (e.g., as AT&T does for cellular units), it may not beable to make TCP connections to the ports. But with OnDemand the devicecan do virtually the same thing as with RM. The device makes aconnection to a server, identifies itself (MAC) and the port it isoffering, and then waits for some activity. When a client program wantsto connect to the port, it connects to the server, asks for a MAC/portcombo, and the server connects the two sockets. At that point, theconnection operates just as if the client had connected to port” 800n or900n on the unit.

RM server software may be, for example, written in python and useOpenSSL. OnDemand server software may be, for example, .NET applicationfor Windows. The server software may have complexities to deal withsecurity, identifying the device/port to connect to, etc. In the case ofOnDemand, it is may be a paid service so that the existence of a validlicense should be checked.

LWHB—Light Weight Heart Beat is a protocol. SOUP updates may berelatively costly. A daily update on a cellular unit over HTTPS consumesabout 27 Kbytes of data if there are no updates. Done daily, thatconsumes over 800 K of data which may be on a 2-5 MB/month data plan.LWHB is designed to send a very small amount of data (about 12 bytes),unencrypted, optionally over UDP or TCP, to the host. The host can justrecord the contact (and the source IP address can be helpful) or it canrespond with some actions—like “Do a full update”, “Send status”,“Reboot”, etc.

LWHB is designed such that users can configure their devices to not do afull update every day but do frequent LWHBs (e.g., every 30 minutes).The server side can then enable a full update only when there issomething to be updated.

A gateway device may include support for connection services with amethod whereby the initial IP address to which a device connects, canredirect the unit to another IP address. This allows an initialconnection server to offload connections to many different servers. Theconnection server may use a networked backend database to track whatunits are attached to servers at any given time so that it can performload balancing. Additionally, customer clients may initially connect tothe connectivity server, but they may subsequently be redirected to theserver where the corresponding device is waiting.

The connection server method allows protocols to scale by allowingadditional servers to be added or deleted as necessary.

The LWHB may be extended to allow the host to inform the unit that ithas been requested to attach to the RM or OnDemand server. When itreceives this request, it can be connected to a server and remainattached for up to one heart beat interval awaiting a connection fromits client. Once, the requested unit has connected to the server, theserver will notify the client via email, IM, other protocol messages, ora combination thereof. The client can then connect to the unit viaOnDemand or RM and complete whatever activity is required. Furthermore,the LWHB protocol may allow that units can post that some actionablealarm or warning condition (e.g., exceeding a temperature, location,motion range, or some other fencing condition) has occurred. In thiscase the unit will immediately connect to the OnDemand or RMs server andawait service from its client.

The above methods reduce connection stresses on OnDemand and RM servers.By not remaining continuously connected to the servers, many more unitscan be handled. The cost of this is the latency of a server respondingto client request. For most automated clients, a cadence measured inhours, is likely sufficient for routine operations.

LWHB servers may also include data archiving and retrieval. The datamay, for example, be accessed by customer applications use an XML schemafor data to be stored and retrieved on their behalf on backend databaseservers.

GPS and AGPS data can be received from the unit by the client, eitherdirectly or via a host. The GPS port can use the NEMA ASCII standard tosend the location, time and motion information. The NEMA sequence, in animplementation, repeats once per second. The information can be packagedin an XML wrapper.

Temperature data can be forwarded, for example, as ASCII stringsincluding the sensor number followed by a space followed by the Celsiustemperature as an ASCII expressed real number followed by a linefeed. Ifa temperature limit has been exceeded, the word “ALERT” may be appendedto the sensor string. For example:

1 27.5C

2 33.9C ALERT

In one implementation, the sequence repeats every 10 seconds and ispackaged in an XML wrapper.

The Position and motion sensor report can, for example, return a stringcontaining the instantaneous acceleration and forces in the X, Y, and Zaxis followed by the time and maximum changes in X, Y and Z forces overthe past 24 hours. The forces are ASCII expressed real numbers that arein units of Gs and are packaged in an XML, wrapper. This string willrepeat at a low rate unless a fence has been violated in which case itscadence is increased.

An example of a stable unit might be:

0.1 0.02 0.97 0.01 0.01 0.01

A unit that has been tampered might return:

0.1 0.05 0.78 0.4 0.5 1.0

A power monitoring report can include, for example, a string of fourASCII expressed numbers separated by spaces and packaged in an XMLwrapper. These may report the current supply voltage, the rate of changeof the supply voltage over the last 30 minutes expressed in volts perhour, the peak supply voltage in the past 24 hours, and the minimumvoltage in the last 24 hours.

An example of a stable UPS powered unit might return:

13.50 +0.05 13.56 13.44

A UPS powered unit experiencing a power failure might return

11.60 −1.17 13.55 11.60

A system may also create and transmit DEX fault reports.

In a further example system, text messaging is used as a way to view andmanage cellular gateway device units. There are multiple ways that textmessaging can be utilized in conjunction with gateway device products.

Unit status—a user can text the serial number of a unit to a servicenumber and get back the status for the unit having that service number.Example status includes the last time the unit contacted SOUP and otheruseful info about the unit. Relatively benign information (not exposinganything private about the unit) may be provided, in an implementation,without requiring any authentication or registration. Other informationcan be more private (e.g., the current IP address, configurationinformation, etc.). Such information may require the requester to havepreviously registered her phone number in a SOUP account before accessis allowed.

Status information may be supplied without communicating with thegateway device unit by supplying information stored at the server. SMSmessages to the server can also schedule a reboot, update, etc.

Commands to the unit—A gateway device unit may be capable of receivingSMS (text) messages. The SMS messages may contain commands to the unit.The commands generally require secure verification of the source of thecommand. Accordingly, the gateway device unit may include authenticationand encryption functionality.

Status from the unit—A gateway device unit may also be capable ofsending SMS messages. In some situations, SMS messaging may be availablewhen other cellular connectivity is unavailable. Accordingly, thegateway device unit may send SMS messages for certain alerts, forexample, an alert text message indicating an inability to connect to aserver.

Those of skill will appreciate that the various illustrative logicalblocks, modules, units, and algorithm steps described in connection withthe embodiments disclosed herein can often be implemented as electronichardware, computer software, or combinations of both. To clearlyillustrate this interchangeability of hardware and software, variousillustrative components, blocks, modules, and steps have been describedabove generally in terms of their functionality. Whether suchfunctionality is implemented as hardware or software depends upon theparticular constraints imposed on the overall system. Skilled personscan implement the described functionality in varying ways for eachparticular system, but such implementation decisions should not beinterpreted as causing a departure from the scope of the invention. Inaddition, the grouping of functions within a unit, module, block, orstep is for ease of description. Specific functions or steps can bemoved from one unit, module, or block without departing from theinvention.

The various illustrative logical blocks, units, steps and modulesdescribed in connection with the embodiments disclosed herein can beimplemented or performed with a processor, such as a general purposeprocessor, a digital signal processor (DSP), an application specificintegrated circuit (ASIC), a field programmable gate array (FPGA) orother programmable logic device, discrete gate or transistor logic,discrete hardware components, or any combination thereof designed toperform the functions described herein. A general-purpose processor canbe a microprocessor, but in the alternative, the processor can be anyprocessor, controller, microcontroller, or state machine. A processorcan also be implemented as a combination of computing devices, forexample, a combination of a DSP and a microprocessor, a plurality ofmicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration.

The steps of a method or algorithm and the processes of a block ormodule described in connection with the embodiments disclosed herein canbe embodied directly in hardware, in a software module executed by aprocessor, or in a combination of the two. A software module can residein RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory,registers, hard disk, a removable disk, a CD-ROM, or any other form ofstorage medium. An exemplary storage medium can be coupled to theprocessor such that the processor can read information from, and writeinformation to, the storage medium. In the alternative, the storagemedium can be integral to the processor. The processor and the storagemedium can reside in an ASIC. Additionally, device, blocks, or modulesthat are described as coupled may be coupled via intermediary device,blocks, or modules. Similarly, a first device may be described atransmitting data to (or receiving from) a second device when there areintermediary devices that couple the first and second device and alsowhen the first device is unaware of the ultimate destination of thedata.

The above description of the disclosed embodiments is provided to enableany person skilled in the art to make or use the invention. Variousmodifications to these embodiments will be readily apparent to thoseskilled in the art, and the generic principles described herein can beapplied to other embodiments without departing from the spirit or scopeof the invention. Thus, it is to be understood that the description anddrawings presented herein represent a presently preferred embodiment ofthe invention and are therefore representative of the subject matterthat is broadly contemplated by the present invention. It is furtherunderstood that the scope of the present invention fully encompassesother embodiments that may become obvious to those skilled in the artand that the scope of the present invention is accordingly limited bynothing other than the appended claims.

What is claimed is:
 1. A method of improving signal reliability of acellularly-connected host device, comprising: monitoring, by a hostdevice, a signal reliability of a cellular module for a signalreliability event; detecting, by the host device, the signal reliabilityevent based on the monitored signal reliability reaching an eventthreshold; providing data regarding the signal reliability event to aremote server; receiving, by the remote server, the data regarding thesignal reliability event; upon the detection of the signal reliabilityevent, performing, by the host device, each of the following steps:issuing a command to the cellular module to re-establish connection witha first cellular network; and restarting the cellular module;accumulating the data regarding the signal reliability with previouslyreceived data regarding prior signal reliability; adjusting, by theremote server, the event threshold based on the accumulated data;transmitting, by the remote server, the adjusted event threshold to thehost device; and updating, by the host device, the event threshold basedon the received adjusted event threshold; wherein a modem providescellular communications capabilities to the host device.
 2. The methodof claim 1, wherein the signal reliability comprises at least one of aviability of network connection, a signal strength, a signal quality, ora signal delay.
 3. The method of claim 1, wherein providing the dataregarding the signal reliability event to the remote server furthercomprises providing at least one of a cellular module identifier, a SIMcard identifier, a host device identifier, and a modem identifier. 4.The method of claim 3, wherein the cellular module identifier comprisesat least one of an IMEI number or an IMSI number.
 5. The method of claim3, wherein the SIM card identifier is an ICCID.
 6. The method of claim1, further comprising: sending, by the modem, device data over a firstlink; characterizing, by the host device, the signal reliability eventas the data regarding the signal reliability event; and sending the dataregarding the signal reliability event to the remote server.
 7. Themethod of claim 1, wherein a first link and a second link are operatedsimultaneously and wherein operating the second link does not interferewith the operation of the first link.
 8. The method of claim 6, furthercomprising changing transmission of device data from sending over thefirst link to sending over a second link.
 9. The method of claim 7,further comprising encrypting the device data, and sending the encrypteddevice data over the second link.
 10. The method of claim 6, wherein thesignal reliability data is encrypted prior to sending, and whereinsending encrypted signal reliability data to the remote server comprisesauthenticating the host device with the remote server.
 11. The method ofclaim 6, further comprising encrypting at least one of the dataregarding the signal reliability event and the device data.
 12. Themethod of claim 6, wherein the device data is sent to the remote server.13. The method of claim 1, further comprising providing a modem thatcoupled to the cellular module and a processor.
 14. A system comprising:a host device comprising a cellular module and a processor configured toperform the logical functions of: monitoring signal reliability of thecellular module for a signal reliability event; providing the signalreliability event to a remote server; upon detection of the signalreliability event, perform each the following steps: issuing a commandto the cellular module to re-establish connection with a first cellularnetwork; and restarting the cellular module; and the remote serverconfigured to perform the logical functions of: accumulating the dataregarding the signal reliability event with previously received dataregarding prior signal reliability events; adjusting an event thresholdbased on the accumulated data; and transmitting the adjusted eventthreshold to the host device; and the host device further configured toperform the logical function of updating the event threshold based onthe received adjusted event threshold.
 15. A method of improving signalreliability of a cellularly-connected host device, comprising:monitoring a signal reliability of a cellular module for a signalreliability event; detecting the signal reliability event based on themonitored signal reliability reaching an event threshold; providing dataregarding the signal reliability event to a remote server; upon thedetection of the signal reliability event, performing each of thefollowing steps: issuing a command to the cellular module tore-establish connection with a first cellular network; and restartingthe cellular module; accumulating the data regarding the signalreliability with previously received data regarding prior signalreliability; adjusting the event threshold based on the accumulateddata; and updating the event threshold based on the received adjustedevent threshold; wherein a modem provides cellular communicationscapabilities to the host device.